科学家发现宇宙膨胀的证据

 　　科学家发现宇宙膨胀的证据

　　WASHINGTON, March 17 (Xinhua) -- U.S. astronomers¹ announced Monday they have captured the first images of gravitational waves, or ripples² in space-time described as the "first tremors³"" of the Big Bang in which the universe came into existence 14 billion years ago.

　　The researchers believed that the results represent the first direct evidence of cosmic inflation, a theory that say the universe expanded by 100 trillion trillion times in less than the blink of an eye in the first fleeting⁴ fraction of a second after the Big Bang.

　　"This work offers new insights into some of our most basic questions: Why do we exist? How did the universe begin?" Harvard- Smithsonian Center for Astrophysics theorist Avi Loeb said in a statement.

　　Scientists find first direct evidence of cosmic inflation

　　"These results are not only a smoking gun for inflation, they also tell us when inflation took place and how powerful the process was," Loeb said.

　　These groundbreaking results came from observations by the BICEP2 telescope at the South Pole of the cosmic microwave background, a faint glow left over from the Big Bang. Tiny fluctuations⁵ in this afterglow provide clues to conditions in the early universe. For example, small differences in temperature across the sky show where parts of the universe were denser⁶, eventually condensing into galaxies⁷ and galactic clusters.

　　But as theorized, inflation should also produce gravitational waves, ripples in space-time propagating throughout the universe. Observations from the BICEP2 telescope at the South Pole now demonstrate that gravitational waves were created in abundance during the early inflation of the universe.

　　On Earth, light can become polarized by scattering⁸ off surfaces, such as a car or pond, causing the glare that polarized sunglasses are designed to reduce. In space, the radiation of the cosmic microwave background, influenced by the squeezing of gravitational waves, was scattered⁹ by electrons, and became polarized, too.

　　Because gravitational waves have a "handedness," they can have both left- and right-handed polarizations and leave behind a characteristic pattern of polarization on the cosmic microwave background known as B-mode polarization.

　　"The swirly¹⁰ B-mode pattern of polarization is a unique signature of gravitational waves," said collaboration¹¹ co-leader Chao-Lin Kuo of Stanford University. "This is the first direct image of gravitational waves across the primordial¹² sky."

　　The team traveled to the South Pole to take advantage of its cold, dry, stable air to examine spatial¹³ scales on the sky spanning about one to five degrees, two to ten times the width of the full Moon.

　　"The South Pole is the closest you can get to space and still be on the ground," said John Kovac of the Harvard-Smithsonian Center for Astrophysics, project co-leader and BICEP2 principal investigator¹⁴. "It's one of the driest and clearest locations on Earth, perfect for observing the faint microwaves from the Big Bang."

　　They were "surprised" to detect a B-mode polarization signal " considerably¹⁵ stronger than many cosmologists expected."

　　The researchers said they analyzed¹⁶ their data for more than three years in an effort to rule out any errors. They also considered whether dust in our galaxy¹⁷ could produce the observed pattern, but the data suggest this is "highly unlikely."

　　Several physicists¹⁸ noted¹⁹ that this could be a Nobel Prize level discovery.

　　"This certainly would rank with the most important discoveries in cosmology over the past 25 years, two of which have already won Nobel Prizes," Lawrence Krauss, professor of Arizona State University, wrote in an email to Xinhua.

1 astronomers   

n.天文学者，天文学家( astronomer的名词复数 )

参考例句：

• Astronomers can accurately foretell the date,time,and length of future eclipses. 天文学家能精确地预告未来日食月食的日期、时刻和时长。 来自《简明英汉词典》
• Astronomers used to ask why only Saturn has rings. 天文学家们过去一直感到奇怪，为什么只有土星有光环。 来自《简明英汉词典》

2 ripples   

逐渐扩散的感觉( ripple的名词复数 )

参考例句：

• The moon danced on the ripples. 月亮在涟漪上舞动。
• The sea leaves ripples on the sand. 海水在沙滩上留下了波痕。

3 tremors   

震颤( tremor的名词复数 )； 战栗； 震颤声； 大地的轻微震动

参考例句：

• The story was so terrible that It'sent tremors down my spine. 这故事太可怕，它使我不寒而栗。
• The story was so terrible that it sent tremors down my spine. 这故事太可怕，它使我不寒而栗。

4 fleeting   

adj.短暂的，飞逝的

参考例句：

• The girls caught only a fleeting glimpse of the driver.女孩们只匆匆瞥了一眼司机。
• Knowing the life fleeting,she set herself to enjoy if as best as she could.她知道这种日子转瞬即逝，于是让自已尽情地享受。

5 fluctuations   

波动，涨落，起伏( fluctuation的名词复数 )

参考例句：

• He showed the price fluctuations in a statistical table. 他用统计表显示价格的波动。
• There were so many unpredictable fluctuations on the Stock Exchange. 股票市场瞬息万变。

6 denser   

adj. 不易看透的, 密集的, 浓厚的, 愚钝的

参考例句：

• The denser population necessitates closer consolidation both for internal and external action. 住得日益稠密的居民，对内和对外都不得不更紧密地团结起来。 来自英汉非文学 - 家庭、私有制和国家的起源
• As Tito entered the neighbourhood of San Martino, he found the throng rather denser. 蒂托走近圣马丁教堂附近一带时，发现人群相当密集。

7 galaxies   

星系( galaxy的名词复数 )； 银河系； 一群（杰出或著名的人物）

参考例句：

• Quasars are the highly energetic cores of distant galaxies. 类星体是遥远星系的极为活跃的核心体。
• We still don't know how many galaxies there are in the universe. 我们还不知道宇宙中有多少个星系。

8 scattering   

n.[物]散射；散乱，分散；在媒介质中的散播adj.散乱的；分散在不同范围的；广泛扩散的；（选票）数量分散的v.散射(scatter的ing形式)；散布；驱散

参考例句：

• The child felle into a rage and began scattering its toys about. 这孩子突发狂怒，把玩具扔得满地都是。 来自《简明英汉词典》
• The farmers are scattering seed. 农夫们在播种。 来自《简明英汉词典》

9 scattered   

adj.分散的，稀疏的；散步的；疏疏落落的

参考例句：

• Gathering up his scattered papers,he pushed them into his case.他把散乱的文件收拾起来，塞进文件夹里。

10 swirly   

成涡旋形的

参考例句：

• There is now a black swirly animation when a spell is resisted. 当法术被抵抗的时候有一个黑色旋涡形的效果。 来自互联网

11 collaboration   

n.合作，协作；勾结

参考例句：

• The two companies are working in close collaboration each other.这两家公司密切合作。
• He was shot for collaboration with the enemy.他因通敌而被枪毙了。

12 primordial   

adj.原始的；最初的

参考例句：

• It is the primordial force that propels us forward.它是推动我们前进的原始动力。
• The Neanderthal Man is one of our primordial ancestors.的尼安德特人是我们的原始祖先之一.

13 spatial   

adj.空间的，占据空间的

参考例句：

• This part of brain judges the spatial relationship between objects.大脑的这部分判断物体间的空间关系。
• They said that time is the feeling of spatial displacement.他们说时间是空间位移的感觉。

14 investigator   

n.研究者，调查者，审查者

参考例句：

• He was a special investigator for the FBI.他是联邦调查局的特别调查员。
• The investigator was able to deduce the crime and find the criminal.调查者能够推出犯罪过程并锁定罪犯。

15 considerably   

adv.极大地；相当大地；在很大程度上

参考例句：

• The economic situation has changed considerably.经济形势已发生了相当大的变化。
• The gap has narrowed considerably.分歧大大缩小了。

16 analyzed   

v.分析( analyze的过去式和过去分词 )；分解；解释；对…进行心理分析

参考例句：

• The doctors analyzed the blood sample for anemia. 医生们分析了贫血的血样。 来自《简明英汉词典》
• The young man did not analyze the process of his captivation and enrapturement, for love to him was a mystery and could not be analyzed. 这年轻人没有分析自己蛊惑著迷的过程，因为对他来说，爱是个不可分析的迷。 来自《简明英汉词典》

17 galaxy   

n.星系；银河系；一群(杰出或著名的人物)

参考例句：

• The earth is one of the planets in the Galaxy.地球是银河系中的星球之一。
• The company has a galaxy of talent.该公司拥有一批优秀的人才。

18 physicists   

物理学家( physicist的名词复数 )

参考例句：

• For many particle physicists, however, it was a year of frustration. 对于许多粒子物理学家来说，这是受挫折的一年。 来自英汉非文学 - 科技
• Physicists seek rules or patterns to provide a framework. 物理学家寻求用法则或图式来构成一个框架。

19 noted   

adj.著名的，知名的

参考例句：

• The local hotel is noted for its good table.当地的那家酒店以餐食精美而著称。
• Jim is noted for arriving late for work.吉姆上班迟到出了名。